Calcium gluconate is used for treating individuals having low levels of calcium ions in their blood system. Often the calcium gluconate is administered orally. However, in more serious calcium deficiency conditions, it is necessary to rapidly increase the amount of calcium ions in the person's blood system which requires administration of calcium via intravenous means. When the individual with the hypocalcemia is a child, in a pediatric intensive care unit, it is almost by necessity that the calcium gluconate is administered intravenously. In severe cases, there could be life threatening complications including cardiac arrhythmias.
Calcium gluconate is an old drug dating back to at least the 1930s, and is available as aqueous solutions of calcium gluconate in 10 mL glass vials and 100 mL rigid plastic bottles. Calcium gluconate is sold as a supersaturated solution which must be administered at a slow rate. The glass vials have a number of disadvantages. First, is the possibility of breakage with the scattering of glass particles. Second, for glass vials and plastic bottles it is necessary to often dilute the calcium gluconate solution in an IV bag so as to allow intravenous (IV) administration at the appropriate rate. Finally, both the glass and rigid plastic containers take up more storage space than the flexible plastic bag products used for IV administration of drugs and other solutions.
Mixtures of calcium gluconate with calcium saccharate are described in U.S. Pat. No. 1,965,535. This patent teaches preparing calcium gluconate solutions containing calcium saccharate as a stabilizer which can be stored in glass containers after suitable sterilization or the use of a preservative agent. The patent cautions that the solution must be protected from “infection” since fermentation readily occurs in the presence of microorganisms.
Hospitals avoid the use of glass and rigid plastic vials and bottles in patient rooms and either will directly transfer the calcium gluconate from the container into plastic bags, which are then used for IV administration or have such bags prepared in advance by adding the calcium gluconate solution to an IV solution. Such pre-prepared bags may be done at the hospital or by a compounder. However the bags so prepared have a limited shelf life at room temperature, typically on the order of about 45 to 70 days. Unused product cannot be used after the expiration date and must be properly disposed of. As a result, hospitals cannot maintain a significant inventory of the calcium gluconate in the plastic IV bags but must often replenish their supply.
In contrast, the calcium gluconate solutions sold in glass and rigid plastic vials are reported to have shelf lives of about three years. Thus, there exists a need for a calcium gluconate aqueous solution product in plastic bags which has a long shelf life.